| 摘要 |
PURPOSE:To sufficiently flatten the surface of a semiconductor substrate or of an interlayer insulating film after embedding a conductive layer in a trench or a contact hole. CONSTITUTION:A silicon nitride film 22 is formed on the surface of a silicon substrate 21, a TEOS film is formed on this silicon nitride film 22 followed by providing the silicon nitride film 22, the TEOS film and the silicon substrate 21 with the first and second opening hole parts and a trench 21a. Next, a second polysilicon film 27 is accumulated in the first and second opening hole parts and in the trench 21a and the TEOS film followed by etching the second polysilicon film 27 so as to position the surface of the polysilicon film 27 on the first opening hole part in order to remove the TEOS film. Next, a thickness for etching of the polysilicon film 27 is set up to the film thickness of the silicon nitride film 22 so as to subject the polysilicon film 27 to isotropic etching. Next, the silicon nitride film 22 is removed. Accordingly, the surface of the semiconductor substrate is sufficiently flattened. |
